JP2011116596A - Fired film for glass production vessel, glass production vessel, glass production device, method for producing glass and method for producing glass production device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a film for a glass production vessel which sufficiently suppresses the generation of bubbles caused by water present in a glass melt. <P>SOLUTION: The fired film 12 for glass producing vessel is formed on the surface 11c of a vessel body 11 made of a noble metal or an alloy including a noble metal. The fired film 12 for a glass production vessel is obtained by filling slurry including a castable and glass particles into a space between the vessel body 11 and a refractory vessel 15, performing drying and firing the slurry, wherein its porosity is ≤5%. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a fired coating for a glass manufacturing container, a glass manufacturing container including the same, a glass manufacturing apparatus including the same, a method for manufacturing glass using the glass manufacturing apparatus, and a method for manufacturing the glass manufacturing apparatus. Specifically, the present invention relates to a fired coating of a glass production container comprising a container body made of a noble metal or an alloy containing a noble metal, and a fired film formed on the surface of the container body, and a glass production container comprising the same. The glass manufacturing apparatus provided with this, The manufacturing method of the glass using the glass manufacturing apparatus, and the manufacturing method of the glass manufacturing apparatus

  Conventionally, as a glass production container for producing high-quality glass such as optical glass and display glass, a glass production container made of a noble metal such as Pt or an alloy containing a noble metal (hereinafter referred to as “noble metal container”). Is used. The reason is that the noble metal container has high rigidity even in a high temperature atmosphere of 1000 ° C. or higher, and hardly contaminates the internal glass.

  However, when a noble metal container is used for melting glass, bubbles due to moisture in the glass may be generated on the surface of the noble metal container on the molten glass side. The reason why this bubble is generated is that oxygen generated by the decomposition of water contained in the glass passes through the noble metal container and is released to the outside, so that the oxygen concentration of the molten glass located near the surface of the noble metal container It is thought that this is because of an increase. That is, molten glass in which hydrogen generated by the reaction shown in the following formula (1) permeates through the noble metal container and is released to the outside, while oxygen having a large atomic size that cannot permeate the noble metal container is located near the surface of the noble metal container. It is considered that the dissolved oxygen increases the oxygen concentration of the molten glass located near the surface of the noble metal container and generates bubbles.

OH ⁻ → 1 / 2O ₂ + 1 / 2H ₂ + e ⁻ (1)

  In view of such a problem, for example, in Patent Documents 1 to 5 below, when a container made of Pt or an alloy containing Pt (hereinafter referred to as “Pt container”) is used, it is caused by moisture in the glass. A method for suppressing the generation of bubbles is proposed.

  For example, in Patent Document 1 below, by controlling the partial pressure of hydrogen outside the Pt container with respect to the partial pressure of hydrogen inside the Pt container at the time of glass production, bubbles caused by moisture in the glass are controlled. A method for suppressing the occurrence has been proposed.

  In the following Patent Documents 2 and 3, a method for suppressing the generation of bubbles due to moisture in the glass by reducing the hydrogen permeability of the Pt container by applying a glass barrier coating to the outer surface of the Pt container is proposed. Has been.

  Moreover, in the following patent document 4, generation | occurrence | production of the bubble resulting from the water | moisture content in glass is suppressed by coat | covering the outer surface of a Pt container with the coating material containing the refractory component containing an alumina and a silica, and a glass component. A method has been proposed.

Special table 2001-503008 gazette JP-T-2004-523449 JP 2006-522001 Gazette WO2006 / 030737 A1

  If it is going to suppress generation | occurrence | production of the bubble resulting from the water | moisture content in glass by the method of said patent document 1, it is necessary to continue supplying hydrogen during glass melting. For this reason, there exists a problem that the manufacturing cost of glass rises. Also, if the hydrogen partial pressure outside the Pt container is too high, hydrogen will pass through the Pt container from the outside of the Pt container and enter the Pt container and melt into the glass melt, which may cause hydrogen bubbles. There is. Therefore, there is a problem that it is difficult to sufficiently suppress the generation of bubbles in the glass melt.

  As described in Patent Documents 2 and 3, when a glass barrier coating layer is formed on the outer surface of the Pt container to suppress the generation of bubbles due to moisture in the glass, hydrogen is generated during glass melting. It is not always necessary to continue to supply. However, as a result of intensive studies by the inventors, it has been found that even when a glass barrier coating layer is formed on the outer surface of the Pt container, the generation of bubbles cannot be sufficiently suppressed. That is, there is a problem that bubbles cannot be sufficiently suppressed by simply forming a glass barrier coating layer on the outer surface of the Pt container.

  As described in Patent Document 4, when the outer surface of the Pt container is coated with a coating material containing a glass component and a refractory component including alumina particles and silica particles, as described in Patent Documents 2 and 3. In addition, a higher hydrogen barrier property can be obtained than when a barrier coating layer made of a glass component is formed. Therefore, generation | occurrence | production of the bubble resulting from the water in a glass melt can be suppressed effectively.

  However, in recent years, the bubble quality required for high-quality glass such as optical glass and display glass has been increasing year by year, and there is a desire to further suppress the generation of bubbles due to water in the glass melt.

  This invention is made | formed in view of this point, The objective is to fully suppress generation | occurrence | production of the bubble resulting from the water which exists in glass melt.

  The fired coating for a glass production container according to the present invention is a fired coating for a glass production container comprising a container body made of a noble metal or an alloy containing a noble metal, and a fired film formed on the surface of the container body. The fired coating for a glass production container according to the present invention is obtained by firing a slurry containing castable and glass particles. The porosity of the fired coating for a glass production container according to the present invention is 5% or less.

  In the fired coating for a glass production container of the present invention, the glass component is mainly responsible for the function of suppressing hydrogen permeation. The castable mainly has a function of holding the glass component. For this reason, if there is a portion in which the glass component does not exist so much in the fired coating for a glass production container, hydrogen permeates from that portion. As a result, bubbles are generated in the glass melt. Therefore, in order to effectively suppress the generation of bubbles in the glass melt, it is necessary to increase the ratio of the glass component present in the fired coating for the glass production container in the film thickness direction.

  Here, in the present invention, the porosity of the fired coating for a glass production container is 5% or less. For this reason, in the film thickness direction, the ratio of the glass component present in the fired coating for a glass production container can be sufficiently increased. In addition, by setting the porosity of the fired coating for a glass production container to 5% or less, the generation rate of continuous pores in the fired coating for the glass production container can be lowered, and the hydrogen shielding property can be improved. Therefore, it is possible to effectively suppress the generation of bubbles in the glass melt.

  On the other hand, if the porosity of the fired coating for a glass production container is greater than 5%, the proportion of the glass component in the fired coating for the glass production container is too low in the film thickness direction. Moreover, the rate of occurrence of continuous pores in the fired coating for glass production containers is increased, and the hydrogen shielding properties are reduced. Accordingly, bubbles are easily generated in the glass melt.

  From the viewpoint of increasing the ratio of the glass component present in the fired film for glass production containers in the film thickness direction and lowering the continuous porosity in the fired film for glass production containers, It is preferred that the porosity is lower. However, if the porosity of the fired coating for a glass production container is too low, the viscosity of the material constituting the fired coating for the glass production container becomes low, and the water contained in the glass component tends to volatilize. Therefore, there exists a tendency for the hydrogen shielding property of the baked film for glass manufacturing containers to fall. Therefore, the porosity of the fired coating for a glass production container is preferably 0.3% or more.

  A more preferable range of the porosity of the fired coating for a glass production container is 0.3% to 4%.

  In the present invention, the method for adjusting the porosity of the fired coating for the glass production container is not particularly limited. For example, the porosity of the fired coating for the glass production container is adjusted by adjusting the content of the alumina component contained in the slurry. be able to. For example, when the silica component is contained in the slurry, the porosity of the fired coating for the glass production container can be adjusted by adjusting the content of the silica component and the content of the alumina component contained in the slurry. . Specifically, the porosity can be lowered by reducing the content of the alumina component in the slurry and increasing the content of the silica component. On the other hand, when the content of the alumina component in the slurry is increased and the content of the silica component is decreased, the porosity is increased.

  Castables are less likely to settle and separate in a slurry than ordinary oxide ceramic particles. For this reason, the heat resistance of the fired coating can be effectively improved by adding castable as an aggregate.

  Examples of the castable include alumina castable, silica castable having a silica content of 40% by mass or more, and SiC castable. Among these, alumina castable is preferable because it has excellent heat resistance, low reactivity with respect to glass, and the porosity can be lowered by adding alumina castable.

  “Castable” refers to a powder obtained by mixing cement and refractory aggregate fired at high temperature. For example, “alumina castable” refers to a powder obtained by mixing alumina cement containing alumina as a main component (that is, alumina content of 40% by mass or more) and high-temperature fired refractory aggregate.

  In the present invention, the contents of the castable and glass components in the slurry are not particularly limited, and can be appropriately set according to, for example, the use temperature of the fired coating for a glass production container or the composition of the castable and glass components. . The preferable contents of the castable and glass components in the slurry are generally 10% by mass to 50% by mass and 20% by mass to 90% by mass, respectively.

  Specifically, the higher the use temperature of the fired coating for a glass production container, the higher the heat resistance required for the fired coating for a glass production container. For this reason, it is preferable to use a castable and glass component having a high alumina content and to increase the castable content.

  On the other hand, when the use temperature of the baking film for glass production containers is low, the heat resistance required for the baking film for glass production containers is low. Therefore, the castable and glass components used may have a small alumina content, and it is preferable to increase the glass component content.

  For example, when the operating temperature of the fired coating for a glass production container is in the range of 1000 ° C. to 1250 ° C., a castable material containing 40% by mass to 60% by mass of an alumina component is used. It is preferable to make content of a component into 5 mass%-20 mass% and 60 mass%-95 mass%, respectively.

  For example, when the operating temperature of the fired coating for a glass production container is in the range of 1250 ° C. to 1450 ° C., a castable material containing 40% by mass to 80% by mass of an alumina component is used. It is preferable to make content of a component into 10 mass%-50 mass% and 30 mass%-90 mass%, respectively.

  For example, when the use temperature of the fired coating for a glass production container is in the range of 1450 ° C. to 1600 ° C., a castable material containing 60% by mass to 90% by mass of an alumina component is used. It is preferable to make content of a component into 15 mass%-50 mass% and 30 mass%-85 mass%, respectively.

  Although the kind of glass component used in this invention is not specifically limited, As mentioned above, it is preferable to use a glass component with a high softening temperature from a viewpoint of suppressing the omission and outflow of a glass component effectively. Specifically, it is preferable to use a glass component having a softening temperature of 800 ° C. or higher, more preferably a glass component having a softening temperature of 850 ° C. or higher, and more preferably a glass component having a softening temperature of 900 ° C. or higher. The softening temperature refers to a value measured with a macro-type differential thermal analysis (DTA) apparatus.

  Specific examples of the glass component having a high softening temperature include borosilicate glass and silicate glass. Among them, it is more preferable to use borosilicate glass or silicate glass having a low content of alkali components such as Na, K, Li, and alkaline earth components such as Ba, Sr, and Ca as glass components. Furthermore, it is more preferable to use a silicate glass having a small content of an alkaline component such as Na, K, Li, or an alkaline earth component such as Ba, Sr, or Ca as the glass component. It is more preferable to use a so-called alkali-free glass component which does not contain.

For example, the composition range of the preferable glass component when the operating temperature of the fired coating for a glass production container is in the range of 1000 ° C. to 1250 ° C. is SiO ₂ 40 to 70 mass%, Al ₂ O ₃ 1 to 30 mass%. , B ₂ O ₃ 1-30% by mass.

For example, when the use temperature of the fired coating for a glass production container is in the range of 1250 ° C. to 1450 ° C., the preferable composition range of the glass component is SiO ₂ 50 to 70 mass%, Al ₂ O ₃ 5 to 30 mass%. , B ₂ O ₃ 1-25% by mass.

For example, when the use temperature of the fired coating for a glass production container is in the range of 1450 ° C. to 1600 ° C., the preferable composition range of the glass component is 50 to 70% by mass of SiO _{2 and} 10 to 30% by mass of Al ₂ O _3. , B ₂ O ₃ 5-20% by mass.

  In the present invention, the slurry for forming a fired coating for a glass production container has colloidal silica as an ingredient for holding the glass component, and alumina having an average particle diameter of 1 μm to 100 μm, instead of a part of the castable. It is preferable to include at least one of particles and silica particles having an average particle diameter in the range of 1 μm to 100 μm. By including at least one of colloidal silica, alumina particles having an average particle diameter of 1 μm to 100 μm, and silica particles having an average particle diameter in the range of 1 μm to 100 μm in the slurry, the fired coating for a glass production container Stiffness and strength can be further increased.

  In addition, since colloidal silica also functions as an inorganic binder, by including colloidal silica in the slurry, the adhesion of the fired coating for glass production containers to the container body can be improved, and the fired coating for glass production containers The denseness of can be improved. Therefore, it can suppress more effectively that a bubble generate | occur | produces in glass melt.

  In the present invention, “colloidal silica” refers to a liquid in which silica fine particles having an average particle diameter of 1 nm to 30 nm are dispersed in a dispersion medium.

The “average particle diameter” means D ₅₀ (volume-based average value), which is a value measured by a laser diffraction / scattering particle size distribution analyzer.

  In the present invention, the shape of the alumina particles added to the slurry separately from the castable is not particularly limited, and may be, for example, spherical or fibrous. That is, alumina fiber may be added to the slurry. In addition, an alumina fiber is not limited to what consists only of alumina, For example, 60 mass% or more of alumina may be included.

  In the present invention, the film thickness of the fired coating for a glass production container is not particularly limited, but is preferably about 100 μm to 10 mm, more preferably about 1 mm to 7 mm, and more preferably about 4 to 6 mm. Is more preferable. If the film thickness of the fired coating for a glass production container is too thin, it may not be possible to sufficiently suppress the generation of bubbles in the molten glass. On the other hand, even if the film thickness of the fired coating for the glass production container is increased more than necessary, the hydrogen shielding property of the fired coating for the glass production container is hardly improved, and the cost and workability tend to be inferior.

  A glass production container according to the present invention includes a fired coating for a glass production container according to the present invention, and a container body made of a noble metal or an alloy containing a noble metal, wherein the fired coating for the glass production container is formed on the outer surface. It has.

  As described above, the fired coating for a glass production container of the present invention has low hydrogen permeability. Therefore, it can suppress effectively that a bubble generate | occur | produces in glass melt by using the glass manufacturing container of this invention provided with the baked film for glass manufacturing containers.

  The glass production container of the present invention may have only the fired film for the glass production container of the present invention as the hydrogen permeation suppression film formed on the outer surface of the container body, or the glass of the present invention. In addition to the fired coating for production containers, another hydrogen permeation suppressing film may be further included. For example, in addition to the fired film for glass production containers of the present invention, the fired film described in Patent Document 4 may be further formed. In that case, it is preferable to form the fired film of patent document 4 on the outer surface of a container main body, and to form the fired film for glass manufacturing containers of this invention on it further.

  In the present invention, the “glass production container” means a member that has an inner surface that contacts the glass melt and an outer surface that does not contact the glass melt and can hold the glass melt. The “glass production container” includes a container capable of holding a glass melt, a pipe capable of conveying the glass melt, a molding member, and the like. Here, the “forming member” refers to a member used for forming a glass melt into a predetermined shape. Accordingly, the “molding member” includes a molding sleeve, a bowl-shaped molded body used in the overflow down draw method, a nozzle, and the like.

  In the present invention, the container body is not particularly limited as long as it is made of a noble metal or an alloy containing a noble metal. However, since the glass manufacturing container of the present invention is used in a high temperature atmosphere, the container body preferably has a certain degree of rigidity in a high temperature atmosphere. The container body is preferably made of, for example, Pt or an alloy containing Pt. Specific examples of the alloy containing Pt include a Pt / Rh alloy, a Pt / Au alloy, a Pt / Pd alloy, and a Pt / Ir alloy.

  Moreover, in order to improve the rigidity of a container main body, other metals, such as Zr and Ti, may be doped in the container main body, for example. That is, in the present invention, the container body may be doped with other elements in the noble metal or an alloy containing the noble metal.

  The glass manufacturing apparatus which concerns on this invention is equipped with the glass manufacturing container which concerns on the said this invention. Therefore, by using the glass manufacturing apparatus according to the present invention, a glass with few bubbles remaining inside the glass can be manufactured.

  The glass production apparatus of the present invention includes a melting container for melting a glass raw material, a fining container for clarifying molten glass, and a stirring container for stirring the clarified glass melt, A member for forming the glass melt, a first connecting member in which a connecting passage for connecting the melting container and the clarifying container is formed, and a connection for connecting the clarifying container and the stirring container. A melting container, a fining container, and an agitation container, each including a second connection member having a channel formed therein and a third connection member having a connection channel connecting the agitation container and the molding member; At least one of the container, the forming member, and the first to third connecting members may be constituted by the glass manufacturing container of the present invention. Among them, each of the fining container, the stirring container, the molding member, and the second and third connecting members excluding the melting container and the first connecting member is constituted by the glass manufacturing container of the present invention. It is preferable. According to this structure, it can suppress more effectively that a bubble remains in glass.

  The glass manufacturing method according to the present invention uses the glass manufacturing apparatus according to the present invention. Therefore, according to the glass manufacturing method of the present invention, it is possible to manufacture a glass with less bubbles remaining inside the glass.

  In the present invention, the glass to be produced is not particularly limited, but the present invention is suitably applied to the production of a glass substrate for a display in which it is more strongly desired that bubbles do not remain in the glass.

  The manufacturing method of the glass manufacturing apparatus which concerns on this invention is related with the method for manufacturing the glass manufacturing apparatus which concerns on the said this invention. The manufacturing method of the glass manufacturing apparatus which concerns on this invention is a process which arrange | positions a container main body in a refractory container, a slurry is filled between a container main body and a refractory container, it dries, and the dried slurry And a step of producing a fired film by firing.

  For example, when a fired coating is formed by applying the slurry to the outer surface of the container body, drying and then firing, if the outer surface of the container body is smooth, the adhesion strength of the fired film to the container body will be low There is a case. For this reason, it is preferable that the outer surface of the container body is preliminarily blasted to make the outer surface rough. However, for example, when there is a welded portion on the container body, it is difficult to perform blasting or the like on the outer surface of the welded portion after welding. Therefore, when there is a welded part in the container body, it is difficult to form a fired coating on the outer surface of the welded part.

  On the other hand, in the present invention, the container body is placed in the refractory container, and after the slurry is filled between the container body and the refractory container, the slurry is dried and fired. For this reason, since the fired film is supported by the refractory container, the adhesion of the fired film to the container body is not necessarily high. Therefore, it is not necessary to perform blasting etc. on the outer surface of the container body in advance, and for example, a fired film can be easily formed on the outer surface of the welded portion of the container body.

  In the present invention, the baking of the slurry is preferably performed when the temperature of the glass manufacturing container is increased in order to melt the glass by the glass manufacturing apparatus. This is because the temperature change of the fired film can be suppressed and damage to the fired film can be effectively suppressed as compared with the case where the slurry is fired in advance.

  According to this invention, generation | occurrence | production of the bubble resulting from the water which exists in glass melt can fully be suppressed.

It is a schematic sectional drawing of the container for glass manufacture which concerns on 1st Embodiment. It is a schematic sectional drawing of the pipe for glass melt conveyance which concerns on 2nd Embodiment. It is a schematic block diagram of the glass melting apparatus which concerns on 2nd Embodiment. 2 is a photograph inside a glass manufacturing container in Example 1. FIG. In FIG. 4, bubbles encircled are bubbles present on the surface of the glass melt, not bubbles generated at the interface between the noble metal crucible and the glass melt. 4 is a photograph inside a glass manufacturing container in Example 4. FIG. In FIG. 5, the circled bubbles are bubbles (entrained bubbles) existing inside the glass melt and are not generated at the interface between the noble metal crucible and the glass melt. 2 is a photograph inside a glass manufacturing container in Comparative Example 1. FIG. 6 is a photograph inside a glass manufacturing container in Comparative Example 2. FIG. 6 is a photograph inside a glass manufacturing container in Comparative Example 4;

  Hereinafter, although an example of the preferable form which implemented this invention is demonstrated, this invention is not limited to the following embodiment.

(First embodiment)
FIG. 1 is a schematic cross-sectional view of a glass manufacturing container according to a first embodiment. In the present embodiment, a glass manufacturing container 10 which is a kind of glass manufacturing container will be described with reference to FIG.

  As shown in FIG. 1, the glass manufacturing container 10 includes a container body 11 disposed in a refractory container 15. The container body 11 is made of a noble metal or an alloy containing a noble metal. Specific examples of the noble metal include Pt, Au, Pd, Rh, Ir, and the like. An example of an alloy containing a noble metal includes an alloy containing Pt. Especially, it is preferable that the container main body 11 is formed with the alloy containing Pt or Pt. This is because Pt or an alloy containing Pt has a relatively high strength at high temperatures. Specific examples of the alloy containing Pt include a Pt / Rh alloy, a Pt / Au alloy, a Pt / Pd alloy, and a Pt / Ir alloy.

  Further, the container body 11 may be doped with other elements such as Zr and Ti for the purpose of improving rigidity and strength. For example, the container body 11 may be made of Pt doped with at least one of Zr and Ti.

  In this embodiment, the container main body 11 is formed in a bowl shape, and the container main body 11 is formed with a recess 11a in which the glass melt 14 is stored. That is, the container body 11 constitutes the surface of the recess 11a, and has an inner surface 11b that contacts the glass melt 14 and an outer surface 11c that does not contact the glass melt 14.

  A fired film 12 is formed on the outer surface 11 c of the container body 11. The fired film 12 is a film for suppressing hydrogen in the glass melt from passing through the glass manufacturing container 10 and being released to the outside.

  The fired film 12 is formed by firing a slurry containing castable and glass particles, and has a porosity of 5% or less. For this reason, in the film thickness direction, the ratio of the glass component having hydrogen shielding properties in the fired coating 12 can be made sufficiently high. Moreover, the continuous porosity in the baked film 12 can be made low by setting the porosity of the baked film 12 to 5% or less. Therefore, it can suppress effectively that a bubble generate | occur | produces in glass melt by melting glass using the container 10 for glass manufacture of this embodiment.

  From the viewpoint of increasing the proportion of the glass component in the fired film 12 and lowering the continuous porosity in the fired film 12, it is preferable that the porosity of the fired film 12 is lower. However, if the porosity of the fired film 12 is too low, the viscosity of the material constituting the fired film 12 becomes low, and moisture in the glass component is likely to volatilize. For this reason, it exists in the tendency for the hydrogen shielding property of the baking coating 12 to fall. Therefore, the porosity of the fired coating 12 is preferably 0.3% or more. A more preferable range of the porosity of the fired coating 12 is 0.3% to 4%.

The method for adjusting the porosity of the fired coating 12 is not particularly limited. For example, the porosity is adjusted by adjusting the content of the Al ₂ O ₃ component and the content of the SiO ₂ component contained in the slurry. be able to. Specifically, the porosity can be lowered by reducing the ratio of the content of the Al ₂ O ₃ component to the content of the SiO ₂ component (Al ₂ O ₃ / SiO ₂ ). On the other hand, when the ratio of the content of the Al ₂ O ₃ component to the content of the SiO ₂ component (Al ₂ O ₃ / SiO ₂ ) is increased, the porosity increases. In addition, as a method of increasing the content of the content of the Al ₂ O ₃ component contained in the slurry, a method of using a castable with a high content of the Al ₂ O ₃ component may be used.

  The content of the castable and glass component in the slurry for forming the fired coating 12 is not particularly limited, and can be appropriately set according to, for example, the use temperature of the fired coating 12 or the composition of the castable and glass component. . In general, the preferable contents of the castable and glass components in the slurry are, for example, preferably 10% by mass to 50% by mass and 20% by mass to 90% by mass, respectively.

  Specifically, the higher the operating temperature of the fired film 12, the higher the heat resistance required for the fired film 12. For this reason, it is preferable to use a castable and glass component having a high alumina content and to increase the castable content.

  On the other hand, when the use temperature of the fired film 12 is low, the heat resistance required for the fired film 12 is low. Therefore, the castable and glass components used may have a small alumina content, and it is preferable to increase the glass component content.

  For example, when the use temperature of the fired film 12 is in the range of 1000 ° C. to 1250 ° C., the castable material containing 40% by mass to 60% by mass of the alumina component is used, and the castable and glass component is contained in the slurry. The amount is preferably 5% by mass to 20% by mass and 60% by mass to 95% by mass, respectively.

  For example, when the operating temperature of the fired coating 12 is in the range of 1250 ° C. to 1450 ° C., a castable material containing 40% by mass to 80% by mass of the alumina component is used, and the castable and glass components are contained in the slurry. The amounts are preferably 10% by mass to 50% by mass and 30% by mass to 90% by mass, respectively.

  For example, when the use temperature of the fired coating 12 is in the range of 1450 ° C. to 1600 ° C., a castable material containing 60% by mass to 90% by mass of the alumina component is used, and the castable and glass components are contained in the slurry. The amounts are preferably 15% by mass to 50% by mass and 30% by mass to 85% by mass, respectively.

  In the present embodiment, the type of glass component used for the preparation of the slurry is not particularly limited, but it is preferable to use a glass component having a high softening temperature from the viewpoint of effectively suppressing the dropout or outflow of the glass component. Specifically, it is preferable to use a glass component having a softening temperature of 800 ° C. or higher, more preferably a glass component having a softening temperature of 850 ° C. or higher, and more preferably a glass component having a softening temperature of 900 ° C. or higher.

  Specific examples of the glass component having a high softening temperature include borosilicate glass and silicate glass. Among them, it is more preferable to use borosilicate glass or silicate glass having a low content of alkali components such as Na, K, Li, and alkaline earth components such as Ba, Sr, and Ca as glass components. Furthermore, it is more preferable to use a silicate glass having a small content of an alkaline component such as Na, K, Li, or an alkaline earth component such as Ba, Sr, or Ca as the glass component. It is more preferable to use a so-called alkali-free glass component which does not contain.

For example, when the use temperature of the fired coating 12 is in the range of 1000 ° C. to 1250 ° C., the preferred glass component composition ranges are SiO ₂ 40 to 70 mass%, Al ₂ O ₃ 1 to 30 mass%, B _2. O ₃ is 1 to 30 mass%.

For example, when the use temperature of the fired coating 12 is in the range of 1250 ° C. to 1450 ° C., the preferable composition range of the glass component is SiO ₂ 50 to 70 mass%, Al ₂ O ₃ 5 to 30 mass%, B _2. O ₃ is 1-25 wt%.

For example, when the use temperature of the fired coating 12 is in the range of 1450 ° C. to 1600 ° C., the preferable composition range of the glass component is SiO ₂ 50 to 70% by mass, Al ₂ O ₃ 10 to 30% by mass, B _2. O ₃ 5 to 20 wt%.

  In the slurry for forming the fired film 12, as a component for holding the glass component, instead of a part of the castable, colloidal silica, alumina particles having an average particle size of 1 μm to 100 μm, and an average particle size of 1 μm It is preferable to include at least one of silica particles in a range of ˜100 μm. By including at least one of colloidal silica, alumina particles having an average particle diameter of 1 μm to 100 μm, and silica particles having an average particle diameter in the range of 1 μm to 100 μm in the slurry, rigidity and strength of the fired coating 12 Can be further enhanced.

  In addition, since colloidal silica also functions as an inorganic binder, by including colloidal silica in the slurry, the adhesion of the fired coating 12 to the container body 11 can be enhanced, and the denseness of the fired coating 12 is improved. can do. Therefore, it can suppress more effectively that a bubble generate | occur | produces in glass melt.

  The shape of the alumina particles added to the slurry separately from the castable is not particularly limited, and may be, for example, spherical or fibrous. That is, alumina fiber may be added to the slurry. In addition, an alumina fiber is not limited to what consists only of alumina, For example, 60 mass% or more of alumina may be included.

  The film thickness of the fired coating 12 is not particularly limited, but is preferably about 100 μm to 10 mm, more preferably about 1 mm to 7 mm, and further preferably about 4 to 6 mm. If the film thickness of the fired coating 12 is too thin, it may not be possible to sufficiently suppress the generation of bubbles in the molten glass. On the other hand, even if the film thickness of the fired film 12 is increased more than necessary, the hydrogen shielding property of the fired film 12 is hardly improved, and the cost and workability tend to be inferior.

  Although the production method of the glass manufacturing container 10 of this embodiment is not specifically limited, For example, it can produce in the following ways.

  First, the container body 11 is prepared. Next, the container body 11 is placed in the refractory container 15. Thereafter, with the container body 11 held slightly apart from the refractory container 15, a slurry containing at least a castable and a glass component is filled between the container body 11 and the refractory container 15 and dried. Thereafter, the slurry is fired to form a fired coating 12. In addition, it is preferable to perform this baking process simultaneously when heating the container main body 11 prior to glass melting when starting glass melting. By doing so, it can suppress that the temperature of the baked film 12 changes a lot. As a result, it is possible to prevent the fired coating 12 from being damaged or falling off.

  According to the method for producing the glass manufacturing container 10, the fired coating 12 can be formed regardless of the state of the outer surface of the container body 11. For example, the fired coating 12 can also be formed on the outer surface of the welded portion of the container body 11. Further, it is not necessary to perform blasting or the like on the outer surface of the container body 11 in advance.

(Second Embodiment)
In the said 1st Embodiment, the container 10 for glass manufacture was mentioned as an example and demonstrated as an example of the glass manufacturing container which implemented this invention. However, in the present invention, the glass production container is not limited to the glass production container 10. The glass manufacturing container may be, for example, a pipe for transporting glass melt. In the present embodiment, a glass melt conveying pipe which is a kind of glass manufacturing container will be described with reference to FIG.

  In the description of the present embodiment, members having substantially the same functions as those in the first embodiment are referred to by the same reference numerals, and description thereof is omitted.

  FIG. 2 is a schematic cross-sectional view of the glass melt conveying pipe of the second embodiment. As shown in FIG. 2, in the glass melt conveyance pipe 20 of the present embodiment, the container body 11 is formed in a cylindrical shape. The outer surface 11 c of the container body 11 is covered with the fired coating 12.

Also in this embodiment, since the outer surface 11c of the container main body 11 is covered with the fired coating 12 as in the first embodiment, oxygen gas caused by water or OH ⁻ ions in the glass melt is used. Generation | occurrence | production can be suppressed effectively.

  In the first and second embodiments, the case where only the fired film 12 is formed on the outer surface of the container body 11 has been described. However, the present invention is not limited to this configuration. For example, a coating film other than the fired film 12 may be further formed on the outer surface of the container body 11 in addition to the fired film 12. For example, the fired film 12 may be formed on the outer surface of the container body 11 after the fired film described in Patent Document 4 is formed.

(Third embodiment)
In the present embodiment, a glass manufacturing apparatus using the glass manufacturing container 10 and the glass melt conveying pipe 20 described in the first and second embodiments will be described with reference to FIG. In addition, the glass manufacturing apparatus of this embodiment is an apparatus for shape | molding the glass substrate for a display by the overflow downdraw method.

  As shown in FIG. 3, the glass manufacturing apparatus 1 includes a melting container 31, a fining container 32, a stirring container 33, a pot 34, a molded body 35 (forming body), and a heating element (not shown). I have. The melting container 31 is a container for melting the charged glass raw material (batch). The melting container 31 is connected to the fining container 32 by a first connection passage 36 a formed inside the first connection member 36. The fining container 32 is a container for clarifying the glass melt supplied from the melting container 31. The clarification container 32 is connected to the agitation container 33 by a second connection passage 37 a formed inside the second connection member 37. The stirring container 33 is a container for stirring and homogenizing the clarified glass melt. The stirring container 33 is connected to the molded body 35 by a third connection passage 38 a formed inside the third connection member 38, a pot 34, and a pipe 39.

  In the present embodiment, at least one of the containers 31 to 33, the pot 34, the connection members 36 to 38, the pipe 39, and the molded body 35 is configured by the glass manufacturing container 10 or the glass melt conveying pipe 20. Yes. Specifically, in the present embodiment, the melting container 31 and the molded body 35 are configured by a refractory furnace made of a refractory, and a clarification container 32, a stirring container 33, a pot 34, and connection members 36 to 38 are included. Each of the pipes 39 is constituted by the glass manufacturing container 10 or the glass melt conveying pipe 20. For this reason, according to the glass manufacturing apparatus 1 of this embodiment, the glass by which it was suppressed that a bubble remained in glass can be manufactured.

  The melting container 31 may also be constituted by the glass manufacturing container 10 described above, but it is not always necessary to apply the glass manufacturing container in which the present invention is applied to the container upstream of the fining container 32.

  Hereinafter, the present invention will be described in more detail. However, the present invention is not limited to the following examples, and can be appropriately modified and implemented without departing from the scope of the present invention.

Example 1
<Foaming test>
Three refractory cubes of 5 mm square are arranged on the bottom of an alumina refractory crucible (inner diameter: 60 mm, height: 40 mm), and made of a Pt / Rh alloy containing 10% by mass of Rh. A noble metal crucible (inner diameter: 46 mm, height 40 mm) was arranged. The surface of the noble metal crucible was previously sandblasted.

  Next, a slurry having a composition shown in Table 1 below was filled in a gap between the refractory crucible and the noble metal crucible. Thereafter, the filled slurry was dried at room temperature for about 1 day, and further dried at 80 degrees for about 1 day.

  Next, the noble metal crucible was filled with glass, heated at a rate of 10 ° C./min, held at the test temperature (1500 ° C.) for 1 to 2 hours, and then the inside of the noble metal crucible was visually observed. As a result, the case where bubbles were not observed on the surface of the noble metal crucible (the case where the area ratio of the bubbles was 0% or more and less than 3%) was designated as “◎”. A case where almost no bubbles were observed on the surface of the platinum crucible (a case where the area ratio of the bubbles was 3% or more and less than 10%) was evaluated as “◯”. A case where a large number of bubbles were observed on the surface of the platinum crucible (when the area ratio of the bubbles was 10% or more) was defined as “x”. The observation results are shown in Table 1 below. Moreover, the photograph in the container for glass manufacture in Example 1 is shown in FIG. In FIG. 4, bubbles encircled are bubbles present on the surface of the glass melt, not bubbles generated at the interface between the noble metal crucible and the glass melt.

Incidentally, in Table _{1, Al 2 O 3 / SiO} 2 is the ratio of the SiO ₂ component of the mass of the mass of _Al 2 _{O 3} component contained in the slurry.

  The details of each component used in this example are as follows.

Alumina castable 1;
Al ₂ O ₃ : 78% by mass,
SiO ₂ : 21% by mass,
CaO: 0.05 mass%,
Na ₂ O + K ₂ O + Li ₂ O: 0.5% by mass,
Other: 0.45 mass%
Glass powder: OA-10 manufactured by Nippon Electric Glass Co., Ltd.
Average particle diameter of alumina particles: 50 μm
Average particle diameter of silica fine particles in colloidal silica: 12 nm
Average particle diameter of silica particles: 20 nm

<Porosity measurement>
Next, the porosity of the fired film was measured by the following method.

  First, the slurry used in this embodiment was filled in an refractory crucible made of alumina (inner diameter: 60 mm, height: 40 mm). Then, it dried on the conditions similar to a present Example, and baked. That is, the filled slurry was dried at room temperature for about 1 day, and further dried at 80 ° C. for about 1 day. Next, the temperature was increased at a rate of 10 ° C./min, and calcination was performed at the test temperature (1500 ° C.) for 5 days.

  Thereafter, the fired product of the obtained slurry was taken out from the refractory crucible, and a cube sample of about 20 mm square was cut out from the fired product using a water-cooled cutter.

  Next, after polishing the surface of the sample using a # 120 diamond polishing machine, the porosity was calculated based on the following formula (2). The results are shown in Table 1 below.

  (Porosity (%)) = {((Sample moisture content) − (Sample dry mass)) / ((Sample moisture content) − (Sample water mass))} × 100 (2)

(Examples 2 to 5)
A foaming test and a porosity measurement were performed in the same manner as in Example 1 except that the composition of the slurry used was changed to the composition shown in Table 1 below. The results are shown in Table 1 below. Moreover, the photograph in the container for glass manufacture in Example 4 is shown in FIG. In FIG. 5, the encircled bubbles are bubbles present on the surface of the glass melt, not the bubbles generated at the interface between the noble metal crucible and the glass melt.

(Comparative Example 1)
The foaming test and the porosity measurement were performed in the same manner as in Example 1 except that the fired film was not formed. The results are shown in Table 2 below. Moreover, the photograph in the container for glass manufacture in the comparative example 1 is shown in FIG.

(Comparative Example 2)
A foaming test and a porosity measurement were performed in the same manner as in Example 1 except that a fired film was not formed using a slurry consisting only of alumina castable. The results are shown in Table 2 below. Moreover, the photograph in the container for glass manufacture in the comparative example 2 is shown in FIG.

(Comparative Example 3)
The foaming test and the porosity measurement were performed in the same manner as in Example 1 except that the fired film was formed using a slurry composed only of silica castable. The results are shown in Table 2 below. In addition, the composition of the used silica castable is as follows.

Silica castable;
Al ₂ O ₃ : 29% by mass,
SiO ₂ : 63% by mass,
Other: 8% by mass,

(Comparative Examples 4-6)
A foaming test and a porosity measurement were performed in the same manner as in Example 1 except that the composition of the slurry used was changed to the composition shown in Table 2 below. The results are shown in Table 2 below. Moreover, the photograph in the container for glass manufacture in the comparative example 4 is shown in FIG.

  As shown in Tables 1 and 2 and FIGS. 4 to 8, in Examples 1 to 5 formed by firing a slurry containing an alumina castable and a glass component, and forming a fired film having a porosity of 5% or less, While almost no bubbles were observed in the glass melt, in Comparative Example 1 in which no fired film was formed and in Comparative Examples 2 to 6 in which the porosity exceeded 5%, many bubbles were observed in the glass melt. It was done. From this result, it is possible to effectively suppress the generation of bubbles in the glass melt by firing a slurry containing an alumina castable and a glass component and forming a fired film having a porosity of 5% or less. I understand that I can do it.

  Furthermore, fewer bubbles were observed in Examples 1 to 3 and 5 having a porosity of 4% or less than Example 4 having a porosity of 4.1%. From this, it can be seen that by setting the porosity to 4% or less, it is possible to more effectively suppress the generation of bubbles in the glass melt.

From the results shown in Tables 1 and 2, the porosity is generally correlated with the ratio of the content of the Al ₂ O ₃ component in the slurry to the content of the SiO ₂ component (Al ₂ O ₃ / SiO ₂ ). I understand. Specifically, the porosity can be lowered by reducing the ratio of the content of the Al ₂ O ₃ component to the content of the SiO ₂ component (Al ₂ O ₃ / SiO ₂ ), while Al ₂ O ₃ It can be seen that the porosity can be increased by increasing the ratio of the content of the component to the content of the SiO ₂ component (Al ₂ O ₃ / SiO ₂ ). From the above results, it can be seen that the porosity can be adjusted by adjusting the ratio of the content of the Al ₂ O ₃ component to the content of the SiO ₂ component (Al ₂ O ₃ / SiO ₂ ).

(Examples 6-9, Comparative Examples 7-9)
In Examples 6-9 and Comparative Examples 7-9, the test temperature was set to 1600 ° C., and the composition of the slurry used was changed to the composition shown in Tables 3 and 4 below. The foaming test and the porosity were measured. The results are shown in Tables 3 and 4 below.

  As shown in Tables 3 and 4 above, the porosity of the fired coating formed by firing a slurry containing an alumina castable and a glass component should be 5% or less even when the glass melting temperature is 1600 ° C. Thus, it can be seen that generation of bubbles in the glass melt can be effectively suppressed.

(Examples 10-14, Comparative Examples 10-14)
In Examples 10-14 and Comparative Examples 10-14, the test temperature was set to 1350 ° C., the composition of the slurry used was changed to the composition shown in Table 5 and Table 6 below, and the composition of the alumina castable was changed to the following composition: Except that, the foaming test and the porosity measurement were performed in the same manner as in Example 1. The results are shown in Tables 5 and 6 below.

Alumina castable 2;
Al ₂ O ₃ : 48.0% by mass,
SiO ₂ : 35.0% by mass,
CaO: 14.6% by mass,
Na ₂ O + K ₂ O + Li ₂ O: 1% by mass,
Other: 1.4% by mass

  As shown in Table 5 and Table 6 above, even when the temperature at the time of melting the glass is 1350 ° C., the porosity of the fired film formed by firing the slurry containing the alumina castable and the glass component should be 5% or less. Thus, it can be seen that generation of bubbles in the glass melt can be effectively suppressed.

(Examples 15 and 16, Comparative Examples 15 to 17)
In Examples 15 and 16 and Comparative Examples 15 to 17, the test temperature was set to 1250 ° C., and the composition of the slurry used was changed to the composition shown in Table 7 and Table 8 below. The foaming test and the porosity were measured. The results are shown in Tables 7 and 8 below.

  As shown in Table 7 and Table 8 above, the porosity of the fired coating formed by firing a slurry containing alumina castable and glass components should be 5% or less even when the temperature at the time of glass melting is 1250 ° C. Thus, it can be seen that generation of bubbles in the glass melt can be effectively suppressed.

DESCRIPTION OF SYMBOLS 1 ... Glass manufacturing apparatus 10 ... Container 11 for glass manufacture ... Container main body 11a ... Recessed part 11b ... Inner surface 11c of container main body ... Outer surface 12 of container main body ... Firing film 14 ... Glass melt 15 ... Refractory container 20 ... Glass melt Pipe 31 for liquid conveyance ... Container for melting 32 ... Container for fining 33 ... Container for stirring 34 ... Pot 35 ... Molded body 36 ... First connecting member 36a ... First connecting passage 37 ... Second connecting member 37a ... Second 2 connection passages 38 ... third connection member 38a ... third connection passage 39 ... pipe

Claims (13)

The fired coating of a glass production container comprising a container body made of a noble metal or an alloy containing a noble metal, and a fired film formed on the surface of the container body,
A fired coating for a glass production container, which is obtained by firing a slurry containing castable and glass particles and has a porosity of 5% or less.   The baked film for glass production containers according to claim 1, wherein the porosity is 0.3% or more.   The fired coating for a glass production container according to claim 1 or 2, wherein the castable is an alumina castable.   The fired film for glass production containers according to any one of claims 1 to 3, wherein the slurry further contains colloidal silica.   5. The fired film for a glass production container according to claim 1, wherein the slurry contains at least one of alumina particles and silica particles having an average particle diameter of 1 μm to 100 μm.   A fired film for a glass production container according to any one of claims 1 to 5, and a container body made of a noble metal or an alloy containing a noble metal, wherein the fired film for a glass production container is formed on an outer surface. A glass manufacturing container.   The glass manufacturing container according to claim 6, wherein the container body is made of Pt or an alloy containing Pt.   A glass manufacturing apparatus comprising the glass manufacturing container according to claim 6. A melting container for melting glass raw materials;
A fining container for fining the molten glass;
A stirring vessel for stirring the clarified glass melt;
A molding member for molding the glass melt;
A first connection member in which a connection passage connecting the melting container and the clarification container is formed;
A second connection member in which a connection passage connecting the clarification container and the stirring container is formed;
A third connection member formed with a connection passage for connecting the stirring vessel and the molding member;
The at least one of the said container for melting, the said container for clarification, the said container for stirring, the said member for shaping | molding, and the said 1st-3rd connection member is comprised of the said glass manufacturing container. Glass manufacturing equipment.   The glass manufacturing apparatus according to claim 9, wherein each of the fining container, the stirring container, the molding member, and the second and third connection members is configured by the glass manufacturing container.   The manufacturing method of the glass using the glass manufacturing apparatus as described in any one of Claims 8-10.   The method for producing glass according to claim 11, wherein the glass is a glass substrate for display. It is a manufacturing method of the glass manufacturing apparatus according to any one of claims 8 to 10,
Placing the container body in a refractory container;
Filling the slurry between the container body and the refractory container and drying;
The manufacturing method of a glass manufacturing apparatus provided with the process of producing the said baking film by baking the said dried slurry.